This indicator will illuminate when the front fog lights are on.
See also:
Changing the battery
If required, replace the battery with a genuine spare part having the same specifications.
If a battery with different specifications is fitted, the service intervals given
in the “Service schedule ...
Replacement Parts
Use of genuine parts for normal/scheduled maintenance and repairs is highly recommended
to ensure the designed performance. Damage or failures caused by the use of non-genuine
parts for maintenanc ...
Driving style
Starting
Do not warm the engine with the car at a standstill or at idle or high speed:
under these conditions the engine warms up much more slowly, increasing electrical
consumption and emissions ...